20CRS4

Composition based on ISO 4954:2018; the product edition is unspecified, so confirm the edition applicable to the contract.

ISO 4954:2018, Table B.2 gives heat analysis; A single value is a maximum; a dash is not zero. ; Product-analysis tolerances are listed separately under Table 2/3 of the standard and do not directly widen the heat-analysis composition ranges. ; Optional Al0.020–0.050% to improve cold-heading performance; this is not a universal mandatory minimum. ; Low Si may be agreed in the order, taking hardenability into account; Where hardenability is required, the standard permits limited deviations, except for P/S; C must not exceed 0.01%; see Table 2 for the other requirements.

Mass fraction wt%; Table B.2 heat analysis; see Table 2 separately for product-analysis tolerances. ; Note a: Al≤0.050% may be added to improve cold heading, but is not mandatory by default. ; Note c: A lower Si or a specified Si range may be requested by agreement; specific agreements have not yet been provided and shall not be filled in arbitrarily. ; When hardenability requirements exist, the small deviations permitted in Table B.6/B.7 must be verified separately according to Table 2 and conditions; the default composition range shall not be expanded. ; Elements not listed must not be intentionally added without purchaser consent, except additions needed to finish steelmaking; Unspecified values are not treated as zero. ; Mechanical properties/hardenability have not been supplemented in this batch; Cold heading applicability must be determined in conjunction with dimensions, state, and technical conditions.

ISO 683-18:1996 Bright non-alloy and low-alloy steel products, Table 3 Heat analysis of carburizing steels, mass fraction wt%; This is not a composition confirmation of the 2014 edition. ; This source is a 13-page public excerpt from the official version; complete composition rows and 5 footnotes from Table 3 have been obtained.; Without Table 4 product-analysis tolerances, Tables 7/8 hardenability data and Chapter 8 compositions of steels for quenching and tempering, verification of the entire standard must not be claimed complete.. ; Currently displaying the range for common grades in Table 3. When hardenability requirements are specified, Footnote 1 allows limited deviations except for P/S, with C not exceeding ±0.01% and other elements subject to Table 4; The absence of Table 4 shall not automatically relax ranges, nor shall it be used for the acceptance of H grades. ; Machinability may be improved by adding lead or controlling sulfide shape upon request; Where lead values are not specified, they shall not be filled as zero or assigned an arbitrary range. ; For other carburizing steels, see ISO 683-11:1987; Different suffix names in the 2014 edition shall not be automatically regarded as the same grade in the 1996 edition. ; A lower Si may be agreed upon during inquiry and ordering, provided the impact on mechanical properties is considered; The base ranges in Table 3 are currently used; do not remove the Si lower limit arbitrarily.. ; Elements not listed in the table must not be assumed to have zero content.; Unlisted elements shall not be intentionally added without the buyer's consent (except additions needed to finish steelmaking), and elements affecting properties introduced via scrap steel etc. shall be prevented. ; Clause 7.2.2.1 stipulates that Table 3 is used for heat analysis; Product-analysis tolerances are given in Table 4, which has not been obtained.. Clause 5.1.2 requires killed steel. Carbide spheroidizing annealing conditions required for cold-heading/cold-extrusion are covered separately by ISO 4954; cold-heading applicability cannot be determined solely by composition.

The basis for actual chemical composition is ISO 683-18—1996; The 2014 edition indicated on the webpage has not been verified; do not confirm that the compositions of the two editions are identical based on this. ISO 683-18:1996 Bright non-alloy and low-alloy steel products, Table 3 Heat analysis of carburizing steels, mass fraction wt%; This is not a composition confirmation of the 2014 edition. ; This source is a 13-page public excerpt from the official version; complete composition rows and 5 footnotes from Table 3 have been obtained.; Without Table 4 product-analysis tolerances, Tables 7/8 hardenability data and Chapter 8 compositions of steels for quenching and tempering, verification of the entire standard must not be claimed complete.. ; Currently displaying the range for common grades in Table 3. When hardenability requirements are specified, Footnote 1 allows limited deviations except for P/S, with C not exceeding ±0.01% and other elements subject to Table 4; The absence of Table 4 shall not automatically relax ranges, nor shall it be used for the acceptance of H grades. ; Machinability may be improved by adding lead or controlling sulfide shape upon request; Where lead values are not specified, they shall not be filled as zero or assigned an arbitrary range. ; For other carburizing steels, see ISO 683-11:1987; Different suffix names in the 2014 edition shall not be automatically regarded as the same grade in the 1996 edition. ; A lower Si may be agreed upon during inquiry and ordering, provided the impact on mechanical properties is considered; The base ranges in Table 3 are currently used; do not remove the Si lower limit arbitrarily.. ; Elements not listed in the table must not be assumed to have zero content.; Unlisted elements shall not be intentionally added without the buyer's consent (except additions needed to finish steelmaking), and elements affecting properties introduced via scrap steel etc. shall be prevented. ; Clause 7.2.2.1 stipulates that Table 3 is used for heat analysis; Product-analysis tolerances are given in Table 4, which has not been obtained.. Clause 5.1.2 requires killed steel. Carbide spheroidizing annealing conditions required for cold-heading/cold-extrusion are covered separately by ISO 4954; cold-heading applicability cannot be determined solely by composition.

A match in the materials database does not establish suitability for cold heading or guarantee finished-product strength. Confirmation must consider wire condition, deformation, heat treatment and tests on actual parts.

A match in the materials database does not establish suitability for cold heading or guarantee finished-product strength. Confirmation must consider wire condition, deformation, heat treatment and tests on actual parts.

A match in the materials database does not establish suitability for cold heading or guarantee finished-product strength. Confirmation must consider wire condition, deformation, heat treatment and tests on actual parts.

The original informative-annex table has been checked and is for reference only. Clause 7.1.2 requires chemical composition to be determined under the cited standard; the formal normative composition and applicable edition remain unverified. Do not use it as a delivery guarantee, a reverse-search acceptance criterion or a basis for standard-range carbon equivalent.